Process of manufacturing methyl chlorid.



UNITED STATES PATENT orrroa.

BURRITT S. LACY, OF PERTH AMBOY, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE ROESSLER & HASSLACH OF NEW YORK.

No Drawing.

Perth Amboy, in the county of Middlesex and State of New Jersey, have invented new and useful Improvements in Processes of Manufacturing Methyl Chlorid, of which the following is a specification.

My invention relates we process for the manufacture of methyl-chlorid and refers particularly to the reaction between methane and chlorin, the combination of which I effect in a quiet and economical way.

of methane with the purpose of obtaining one of the four possible chlorids, serious difficulties have interfered with the success of the process. The most important of these difficulties consist in the tendency of chlorin to react explosively with separation of carbon, and in the fact that a mixture of the four chlorids of methane is obtained, from which it is difficult and expensive to isolate the pure substances, which boil at 240, +46", +62, and |78 Centigrade. I have found, however, that by using an excess of methane over and above the theoretical proportions of equal parts by volume of methane and chlorin, the reaction, under certain conditions of temperature and material of reaction chamber pointed out more particularly below, goes smoothly,

without separation of carbon, and in such a way that the chlorin reacts to form the monochlo-rid (EH- C1 almost exclusively with only small amounts of the three other chlorids CH Ch, CHCl and GU1 The process is essentially as follows: Methane and chlorin in'the proportions of, for instance 10 to 1 by volume are allowed to mix just before passing into the reaction vessel which is preferably, maintained at about 400 C. because a higher temperature tends to cause a slight deposition of'carbon which, however, is absolutely avoided at a temperature of about 400 centigrade.

As a material for the reaction vessel I prefer to use glass, quartz, porcelain, earthenware or the like materiah'because even dry chlorin at the aforesaid temperature attacks metals with great rapidity, and,

because by the use of these materials I- avoid.

all decomposition of methane leading to a deposition of carbon on the walls of the Specification 01' Letters Patent.

ER CHEMICAL COMPANY, A CORPORATION PROCESS OF MANUFACTURING METHYL CHLORID.

Patented Sept. 29, 1914.

Application filed m 7, 1913. Serial No. 777,767.

reaction vessel. I have further observed that practically all of the chlorin under these circumstances is combined with, if the gases are passing at such a speed that they are passed through an absorbent such as water It is well known that in the chlorination 1s then removed by passing the gases over a suitable drying agent such as concentrated sulfuric acid whereby the remaining mixture is brought into a state allowing a. separation of the methyl-chlorid from the methane. I have found that this separation can beeffected in a highly satisfactory degree by the employment of certain combinations of pressure and low temperature. For example A. I may cool the mixture of methane and/ methyl-chlorid to a temperature of about -120 C. under a" pressure of about one atmosphere, or B. I may employ a temperature of about ,80 C. with approximately 150 lbs. pressure, or, C. I may employ a temperature of about 30 C. with about 1500 lbs, pressure per square inch.

With any of the above sets of conditions the separation of the methyl-chlorid is substantially complete, and the methane, substantially free from methyl-chlorid, passes on to a gas holder to be subsequently mixed with fresh chlorin to repeatthe whole process. The methyl-chlorid so obtained maybe used directly or may be stored in strong cylinders, the vapor pressure of the liquid being about 5 atmospheres at 20 C.

In connection with A, it should be noted that the methyl-chlorid separates out as a solid; the handling ofwhich presents some mechanical difliculties which do not exist when the material is in the liquid form. As between B and C I prefer B inasmuch as I find it more convenient to avoid the excessive pressure involved in C. It

might be anticipated that at these low temperatures, difiic'ulties might arise on account of the freezing of the trace of higher chlorids formed with the methyl-chlorid. I

have discovered that, as a matter of fact, such difficulties do not arise; even when a considerable amount of carbon tetrachlorid (melting point -30) is present, no solid separates out under the conditions of B, a result due no doubt to the solvent effect of the methyl-chlorid.

It should be noted that the methane may be stored over water, as I have observed that the moisture thereby introduced-into the methane does not prevent the successful operation of my process.

It is understood that I do not in any way limit myself to the exact conditions mentioned in the foregoing, since these may be naturally varied considerably without departing from the general principles of the invention; for example if the volume of methane used is less than ten times the volume of the chlorin, a lower degree of cooling' and pressure than that cited in the foregoing example Will naturally suflice to separate the methyl-chlorid from the unused methane and vice versa.

I claim:

1. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing chlorin gas with a proportion of methane greater than the theoretical one and bringing said mixture to reaction. 2. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing chlorin gas with a proportion of methane greater than the theoretical one, close to the reaction vessel before entering same and causing the mixture to react within a suitable reaction vessel.

3. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing chlorin gas with a proportion of methane greater than the theoretical one, close to the reaction vessel before entering same and causing the mixture to react Within a non-metallic reaction vessel. 4. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing chlorin gas with a proportion of methane, greater than the theoretical one, close to the reaction vessel before entering same and causing the mixture to react within a reaction vessel made of quartz.

5. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing methane with chlorin gas with a proportion of methane, greater than the theoretical one, passing said mixture through a reaction vessel of quartz and maintaining said vessel at a suitable temperature.

6. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing methane with chlorin gas with a proportion of methane greater than the theoretical one, passing said mixture .through a reaction vessel of quartz and maintaining said reaction vessel at a temperature of about 400 centigrade.

7. The process of manufacturing methylchlorid from methane and chlorin gas, consisting in mixing chlorin gas with a proportion of moist methane greater than the theoretical one, passing said mixture through a reaction vessel of quartz and maintaining said reaction vessel at a temperature of about 400 centigrade.

8.'The process of manufacturing methylchlorid from methane and chlorin, consisting in mixing chlorin gas with a proportion of methane greater. than the theoretical one, exposing said gas mixture to a temperature of about 400 C. while passing through a non-metallic reaction vessel, washing the obtained reaction gases with water to remove the hydrochloric acid gas, drying the remaining gases by passing same over a suitable drying agent and separating the methylchlorid from the unused methane by means of suitable cold and pressure.

9. The process of manufacturing methylchlorid from methane and chlorin, consisting in mixing chlorin gas with about ten times its volume of methane, exposing said gas mixture to a temperature of about 400 C. while passing through a non-metallic reaction vessel, Washing the obtained reaction gases with Water to remove the hydrochloric acid gas, drying the remaining gases by passing same over a suitable drying agent, and separating the methyl-chlorid from the unused methane by compressing the mixture to about 150 lbs. of pressure per square inch and cooling the mixture in the compressed state to about 80 C.

. BURRITT S. LACY.

Witnesses:

Orro K. ZWINGENBERGER, ARTHUR L. GARDNER. 

